Bromomethyl-2-thienylketone

A mixture of 4 parts of 2-iminothiazoline, 8.3 parts of bromomethyl-2-thienylketone and 40 parts of absolute ethanol is stirred and refluxed for 2 hours in a water-bath. After cooling, the precipitated hydrobromide is filtered off. From this salt the free base is liberated on treating with ammonium hydroxide solution and it is extracted with chloroform. The organic extract is separated, treated with activated charcoal, filtered and the filtrate is first dried over magnesium sulfate and then evaporated. The solid residue is recrystallized from 24 parts 2-propanol, to yield 2-imino-3-[(2-thienylearbonyl)-methyl]-thiazoline MP 117.5°-118.5°C. 

Bromomethyl-2-thienylketone Sodium borohydride Phosphoroxy chloride... 

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